Adjustable stretcher



May 31, 1966 o. M. ST. JOHN ADJUSTABLE STRETCHER 3 Sheets-Sheet 1 FiledFeb. 8, 1965 INVENTOR OTTO M. ST JOHN BY ATTORNEYS May 31, 1966 o. M.ST. JOHN ADJUSTABLE STRETCHER 3 Sheets-Sheet 2 Filed Feb. 8, 1965INVENTOR.

OTTO M. ST JOHN I W Y ATTORNEYS y 1966 o. M. ST. JOHN 3,253,284

ADJUSTABLE STRETCHER Filed Feb. 8. 1965 3 Sheets-Sheet 5 INVENTOR 5 OTTOM. ST JOHN 7 ATTORNEYS United States Patent 3,253,284 ADJUSTABLESTRETCHER Otto M. St. John, Toledo, Ohio, assignor to Gendron WheelCompany, Toledo, Ohio, a corporation of Dela- Filed Feb. 8, 1965, Ser.No. 4s0,ss2 2 Claims. (Cl. 62)

This invention relates to stretchers but particularly to those which areadjustable so as to alter the position of the patient both from thestandpoint of height and/or Trendelenberg position.

An object is to produce new and improved adjusting mechanism for the bedof a stretcher to regulate the height position and achieve Trendelenbergposture which can be operated easily and shifted conveniently from oneform of adjustment to another; can be manufactured and assembledeconomically; is almost noiseless in operation; and is free of actuatingcomplexities.

Other objects and advantages of the invention will hereinafter appearand, for purposes of illustration but not of limitation, an embodimentof the invention is shown on the accompanying drawings, in which:

FIGURE 1 is a side elevation of the structure equipped with the novelmeans of elevating the bed thereof as well as adjusting it toTrendelenberg position;

FIGURE 2 is an enlarged fragmentary sectional view of the adjustingmechanism and the associated adjustment at the rear end of thestructure;

FIGURE 3 is a fragmentary sectional view showing a portion of theadjusting mechanism for the front end portion of the structure;

FIGURE 4 is a diagrammatic view showing the manner in which the chainsextend about the sprockets for both the rear and front end of thestructure; and

FIGURE 5 is an enlarged fragmentary sectional view of an alternatestructure of mounting the sprocket nut and associated elements.

The illustrated embodiment of the invention comprises a stretcher 10,which has a pair of laterally spaced interconnected upright membersconstituting a frame 11 formed of tubular members,'the same beingsupported on caster wheels 12. Only a single frame member is shown onthe drawings. Each upright frame member 11 has a pair of verticallyspaced horizontal tubular bars 11a and 11b and a pair of horizontallyspaced vertical tubular bars 110 and 11d. Supported by the frame 11 is ahorizontal bed 13, on which is a pad 14. As shOWn, there are uprightposts 15 suitably connected to the bars 11a and 11b and disposed at thefront and rear of each frame member. Although two are shown in FIGURE 1it is to be understood that a similar arrangement is incorporated in theother laterally spaced frame member so that there are four tubularupright posts 15, in which are disposed bed-supporting members. Thus thebed of the stretcher is supported at four points, two at the front andtwo at the rear, as will fully appear hereinafter.

Disposed in each of the four tubular posts is a screwthreaded shaft 16.FIGURE 3 illustrates the connection between the screw-threaded shaftsand the forward end of the bed 13. As shown, a horizontally slottedchannel 17 is welded to the upper end of the respective screwthreadedshafts 16. Depending from the under side of the bed 13 is a U-shapedbracket .18 which embraces a part of the channel 17. The bracket 18 hasa roller 19 carried by a shaft 20, which roller rides in the horizontalslot. The roller 19 is rotatable along the channel of the member 17 whenthe stretcher bed is adjusted to a Trendelenberg position.

The screw-threaded shafts 16 at the rear of the stretcher as shown onFIGURE 2 are welded at their upper ends to upright brackets 21, whichare connected I by a pivot pin 22 to clevis-like brackets 23, which arefixed to and depend from the under side of thebed 13.

Rotatable on each of the four screw-threaded shafts 16 are internallyscrew-threaded nuts or sleeves 24. The lower portion of each nut 24 isenclosed by a sheet metal housing 25, which is welded to the outside ofthe sleeve. At the lower end of the housing 25 is an outwardly extendingflange 26. At the lower end of the housing 25 and abutting against theunder side of the flange 26 is a plate 27 which is secured thereto byscrews 28.

Bearing against the under side of the nut 24 is a ball bearing unit 29contained within a cage 30. For receiving downward thrust from the ballbearing unit 29 is a T- shaped head or flange 31 disposed between theupper side of the plate 27 and the bearing unit. The flange 31 bearsagainst the upper end of the tubular housing 15 and is integral with aplug-like body 32 which fits the inside of the housing 15 and -isapertured freely to receive-the threaded shaft 16. Pins 32' extendthrough the walls of the housing 1 5 and the plug 32 to hold the latterin place. It will be understood that the housing 25 and plate 27 rotatewith the nut 24 and the flange 31 holds these parts against upwardmovement. Movement in the opposite direction is prevented by the flange31 against which the thrust bearing 29 bears.

In each case the nut 24 also serves as a sprocket wheel and integralwith the upper portion thereof is a circular row of sprocket teeth 33.As will hereinafter appear, chains interconnect the two sprocket wheelsat the rear of the stretcher with a driving sprocket and the twosprocket wheels at the front of the stretcher connect by a chain toanother driving sprocket.

An alternate mounting for the sprocket nut is shown on FIGURE 5 in whichthe nut 24a has sprocket teeth 33a and threadedly engages the screwshaft 16. A bearing cup 25a has an outward flange at the top which issecured by series of screws 28a to a plate 27a. The latter is aperturedfreely to receive the nut 24a which has an external annular groove toreceive a retaining ring 24b disposed beneath the plate 27a to militateagainst upward movement of the sprocket nut relative to the bearing cup25a. The cup 25a is secured against movement by being welded to theadjacent post 15. Within the cup 25a is a ball thrust bearing unit 29awhich receives the downward thrust of the nut 24a and resists downwardmovement thereof. The lower race of the bearing unit 29a has a press fitwithin the cup 25a. It will be manifest that turning movement of the nut24a in one direction or the other causes appropriate up or down movementof the screw shaft 16 and the nut is retained against axial movement.

Suitably arranged and supported between the rear pair of tubular legs15, and disposed forwardly thereof, is a driving mechanism. As shown, anupright tubular support 34 has its upper end welded to a housing bracket35. Disposed at the upper end of the housing bracket 35 is a flangebracket 37, which is connected by screws 38 to the top surface of asheet metal housing 39, which, as shown in FIGURE 1, is of substantiallength and width suflicient to cover the actuating mechanism. The openbottom-of the housing 39 is covered by a bottom panel 40 and the housingand panel 40 are secured to the frame 11 by screws 41. Arranged withinthe bracket housing 35 and in superposed axial alignment are sleeves 42and 43, which are separated by a bearing ring 46. The lower end of thesleeve 42 has an integral sprocket wheel 45 and the upper end of thesleeve 43 has an integral sprocket wheel 44.

Concentric of the sleeves 42 and 43 and mounted for up and down movementis an operating shaft 47, the upper end :portion of which operates in aball bearing unit 48 carried by the bracket 35, so as to turn freely andalso to slide axially therethrough. Rigid with the shaft 47 andprojecting outwardly therefrom are longitudinally elongate keys 49,which ride in keyways 50 and 51 in the sleeves 42 and 43 respectively.The arrangement is such that the keys 49 may selectively engage bothsleeves for conjoint operation thereof or engage one or the otherdepending upon the vertical position of the shaft and the arrangement ofkeys with respect to the sleeves. Thus, depending upon the verticalposition of the keys 49, both sleeves 42 and 43 may be rotated together,or one or the other of the sleeves may be independently driven.

At the lower end of the operating shaft 47 is an elongate keyway 52 andextending into this keyway is a key 53 carried by a bevel gear 54. Thisarrangement is such that the operating shaft 47 may be raised or loweredand in any of its vertically adjusted positions the gear 54 mayrotatably drive the shaft 47.

The lower end of the operating shaft 47 is rotatable and longitudinallyslideable in a ball bearing unit. 55, which is carried by a cup-shapedhousing 56 to which the lower end of the tubular support 34 is welded.The open end of the housing 56 is closed by a plate 57 connected theretoby screws 58. Also disposed within the housing is a second bevel gear 59disposed at right angles to the gear 54 and in mesh therewith. The bevelgear 59 is connected to a horizontal drive shaft 60 by a set screw 59.The drive shaft 60 has its opposite end portions rotatable in ballbearing units, a ball bearing unit 61 being shown at the inner endportion of the shaft but the ball bearing unit at the outer end is notshown in the drawings. The drive shaft 60 is disposed within a housingtube 62 which projects through an opening in the cup housing 56 and isflanged thereover, the opposite end portion being suitably supported onthe stretcher frame by means not shown. Suitably connected to the outerend of the drive shaft 60 is an operating crank handle 63.

From the above description it will be understood that by turning thecrank handle 63 the vertical operating shaft 47 is rotated in onedirection or the other through the bevel gears 59 and 54. Rotation ofthe operating shaft 47 imparts movement to one or both of the sprocketgear carrying sleeves 42 and 43 and the sprocket gear 45 has a chain 68common to both of the sprocket gears 33 arranged at the rear portion ofthe stretcher. A chain 69 extends from the sprocket gear 44 to both ofthe sprocket gears 33 at the front portion of the stretcher. It will beunderstood that turning of the sprocket gears 33 in one direction causesthe respective screw shafts to move upwardly, thereby to elevate thatportion of the stretcher bed and rotation of the sprocket gears 33 inthe opposite direction serves to move that portion of the stretcher beddownwardly.

Vertical shifting movement of the operating shaft 47 is effected by ahand lever 64, which is pivoted on a headed bolt 65 connected to theunder side of the drive shaft housing tube 62. The hand lever 64 is ofbent form and of generally V shape. The free end of the lever 64 isforked at 66 to engage an annular groove 67 in the lower end portion ofthe operating shaft 47. Manifestly, by rocking the hand lever in onedirection the operating shaft 47 is moved upwardly and when rocked inthe opposite direction the operating shaft is moved downwardly.

In operation when it is desired to raise or lower the bed 13 uniformlythe hand lever 64 is operated to move the operating shaft 47 to suchposition that the keys 49 engage both sleeves 42 and 43. Then byrotating the crank handle 63 in one direction the bed 13 is raised andin the opposite direction the bed 13 is lowered, this operation beingeffective through the sprocket and chain connections above described. Inorder to adjust the bed 13 of the stretcher to a Trendelenberg positionthe hand lever 64 is operated in order to move the operating shaft 47axially to bring the keys 49 either wholly in engagement with the sleeve43 or wholly in engagement with the sleeve 42. By engagement wholly withthe sleeve 43 and then by'turning the crank arm 63, the front of the bed13 is either moved upwardly or downwardly whereas the rear end portionof the bed 13 remains stationary. This action is effected by the rockingmovement about the pivots 22. Such freedom of movement is made possibleby the connection between the rollers 19 and the horizontally slottedbrackets 17 disposed at the front end portion of the bed.

Similarly, if it is desired to raise or lower only the rear end .of thebed 13, then the operating shaft 47 is shifted to a position so that thekeys 49 are disposed wholly within the sleeves 42, then by turning thecrank arm 63 it will be manifest that the rear end portion only isrocked in the desired direction. It will be further apparent that whenthe bed of the stretcher has been adjusted to a Trendelenberg position,the bed then may be moved upwardly or downwardly in its inclinedposition by then disposing the operating shaft 47 so that the keys 49engage both of the sleeves 42 and 43.

Numerous changes in details of construction, arrangement and operationmay be effected without departing from the spirit of the invention,especially as defined in the appended claims.

What I claim is:

1. A stretcher comprising an upright frame, a bed above said frame,combined support and adjustment means for said bed including verticallydisposed screw shafts connected to said bed and depending therefrom, anut having a sprocket wheel rigid therewith and in screw threadedengagement with each screw shaft, means to mount each nut upon saidframe and retain same against axial movement, means for selectivelyrotating said nuts to effect bed adjustment, said last means comprisingsprocket and chain connections to said sprocket wheels, driving meansfor said sprocket and chain connections comprising a pair of drivingsprocket wheels, chains connecting each driving sprocket with nutcarrying sprocket wheels arranged respectively fore and aft of thestretcher bed so that rotation of one driving sprocket wheel in onedirection raises one end of the bed and in the opposite direction lowerssaid end of the bed, and rotation of the other driving sprocket wheelraises or lowers the opposite end of the bed in accordance with thedirection of rotation, and conjoint rotation of both driving sprocketwheels raises or lowers the bed in the position to which it haspreviously been adjusted, and common means for actuating said drivingsprocket wheels together or for actuating one or the other of saiddriving sprocket wheels.

2. A stretcher comprising an upright frame, a bed above said frame,groups of supporting elements arranged respectively fore and aft of saidframe and pivotally connected to said bed, said supporting elementscomprising vertically disposed screw threaded rods, operating members inthe form of sprocket wheels fixed to nuts contained on the frame andconnected individually to said screw threaded rods respectively andeffecting linear movement of the latter in one direction or the other inresponse to predetermined rotative movements of said screw threaded rodsand driving mechanism for said screw threaded rods, said drivingmechanism comprising sprocket chains and a pair of driving sprocketwheels, the driving sprocket wheels being fixed to axially alignedsleeves, one sprocket chain being common to one driving sprocket wheeland one group of sprocket wheel carrying nuts, and another chain beingcommon to the other group of sprocket wheel carrying nuts and the otherdriving sprocket wheel, and control means for said driving mechanism forselectively establishing an operative drive for one or the other or bothgroups of screw threaded rods thereby to raise or lower the bed in ahorizontal operation, to effect a Trendelenberg position, or to raiseand lower the bed when in a Trendelenberg position, said control meansincluding a rotary shaft slidable axially through said sleeves, keywaysin said sleeves, and a key 1,943,280 on said rotaryshaft to operativelyengage one or be 2,522,759 of said keyways. 2,681,454

References Cited by the Examiner 5 UNITED STATES PATENTS 918,240 4/1909Wheeler 108-147 934,949 9/1909 Trickey et a1. 254-72 Arnold 108-147Lindquist 5-63 Tallman 254--7.2 X

Scher 5-63 FRANK B. SHERRY, Primary Examiner.

C. A. NUN BERG, Assistant Examiner.

1. A STRETCHER COMPRISING AN UPRIGHT FRAME, A BED ABOVE SAID FRAME,COMBINED SUPPORT AND ADJUSTMENT MEANS FOR SAID BED INCLUDING VERTICALLYDISPOSED SCREW SHAFTS CONNECTED TO SAID BED AND DEPENDING THEREFROM, ANUT HAVING A SPROCKET WHEEL RIGID THEREWITH AND IN SCEW THREADEDENGAGEMENT WITH EACH SCREW SHAFT, MEANS TO MOUNT EACH NUT UPON SAIDFRAME AND RETAIN SOME AGAINST AXIAL MOVEMENT, MEANS FOR SELECTIVELYROTATING SAID AGAINST TO EFFECT BED ADJUSTMENT, SAID LAST MEANSCOMPRISING SPROCKET AND CHAIN CONNECTIONS TO SAID SPROCKET WHEELS,DRIVING MEANS FOR SAID SPROCKET AND CHAIN CONNECTIONS COMPRISING A PAIROF DRIVING SPROCKET WHEELS, CHAINS CONNECTING EACH DRIVING SPROCKET WITHNUT CARRYING SPROCKET WHEELS ARRANGED RESPECTIVELY FORE AND AFT OF THESTRETCHER BED SO THAT ROTATION OF ONE DRIVING SPROCKET WHEEL IN ONEDIRECTION RAISES ONE END OF THE BED AND IN THE OPPOSITE DIRECTION LOWERSSAID END OF THE BED, AND ROTATION OF THE OTHER DRIVING SPROCKET WHEELRAISES OR LOWERS THE OPPOSITE END OF THE BED IN ACCORDANCE WITH THEDIRECTION OF ROTATION, AND CONJOINT ROTATION OF BOTH DRIVING SPROCKETWHEELS RAISES OR LOWERS THE BED IN THE POSITION TO WHICH IT HASPREVIOUSLY BEEN ADJUSTED, AND COMMON MEANS FOR ACTUATING SAID DRIVINGSPROCKET WHEELS TOGETHER OR FOR ACTUATING ONE OR THE OTHER OF SAIDDRIVING SPROCKET WHEELS.